perf: enable source-specific asset downloads and make nitro/icon URLs optional

Import improvements:
- importSingleFurni now accepts sourceSwfBaseUrl, nitroBaseUrl, iconBaseUrl
  params to try source-specific asset downloads before falling back to
  the official Habbo CDN (images.habbo.com)
- Source-specific URL cascade:
  1. Try sourceSwfBaseUrl/hof_furni/{rev}/{name}.swf
  2. Try sourceNitroBaseUrl/{name}.nitro (pre-made nitro bundles)
  3. Fallback to images.habbo.com/dcr/hof_furni/{rev}/{name}.swf
- Same fallback chain for icon downloads
- Clone sources can now have empty nitroBaseUrl/iconBaseUrl (retro
  hotels without nitro support)
- Added VirtualCity source (verified SWF downloads via virtualc.nl/dcr)
- Added sourceSwfBaseUrl field to CloneSource interface
- Both batch and single import routes pass source params through
- Clone POST route accepts sourceSwfBaseUrl, makes nitro/icon optional
- Nitro fallback download tries .nitro files before SWF conversion

src/lib/services/furni-import.ts

@@ -383,6 +383,11 @@ export async function importSingleFurni(params: {
 	category: string;
 	skipFurniDataWrite?: boolean;
 	onProgress?: (status: string) => void;
+	/** Per-source SWF download base URL (e.g. "https://virtualc.nl/dcr"). */
+	sourceSwfBaseUrl?: string;
+	/** Per-source nitro bundle + icon base URL. */
+	nitroBaseUrl?: string;
+	iconBaseUrl?: string;
 }): Promise<ImportSingleResult> {
 	const {
 		id: originalId,
@@ -394,6 +399,9 @@ export async function importSingleFurni(params: {
 		category,
 		skipFurniDataWrite,
 		onProgress,
+		sourceSwfBaseUrl,
+		nitroBaseUrl: sourceNitroBaseUrl,
+		iconBaseUrl: sourceIconBaseUrl,
 	} = params;
 	const warnings: string[] = [];
 
@@ -495,33 +503,71 @@ export async function importSingleFurni(params: {
 	// fall back to base-classname icon (Nitro reuses base for all colors
 	// when no color-specific icon exists).
 	onProgress?.("downloading");
+
 	const iconColorAware = classname.replace(/\*/g, "_");
-	const iconUrl = hasColor
-		? `https://images.habbo.com/dcr/hof_furni/${rev}/${encodeURIComponent(iconColorAware)}_icon.png`
-		: `https://images.habbo.com/dcr/hof_furni/${rev}/${encodeURIComponent(baseClassname)}_icon.png`;
 
-	const downloadResults = await Promise.allSettled([
-		downloadFile(iconUrl, iconPath, { validate: "png" }),
-		downloadFile(
-			`https://images.habbo.com/dcr/hof_furni/${rev}/${encodeURIComponent(safeSwfName)}.swf`,
-			swfPath,
-			{ validate: "swf" },
-		),
-	]);
+	// Build candidate URL lists — source-specific URLs first, then Habbo CDN fallback
+	const iconUrls: string[] = [];
+	const swfUrls: string[] = [];
 
-	let iconOk =
-		downloadResults[0].status === "fulfilled" && downloadResults[0].value.ok;
-	const swfOk =
-		downloadResults[1].status === "fulfilled" && downloadResults[1].value.ok;
-
-	// If color-specific icon 404'd, try the base-classname icon.
-	if (!iconOk && hasColor) {
-		const dl = await downloadFile(
-			`https://images.habbo.com/dcr/hof_furni/${rev}/${encodeURIComponent(baseClassname)}_icon.png`,
-			iconPath,
-			{ validate: "png" },
+	// Source-specific icon URLs
+	if (sourceIconBaseUrl) {
+		// e.g. https://habblet.city/nitro/icons/{classname}_icon.png
+		iconUrls.push(
+			`${sourceIconBaseUrl}/${encodeURIComponent(iconColorAware)}_icon.png`,
+			`${sourceIconBaseUrl}/${encodeURIComponent(baseClassname)}_icon.png`,
 		);
-		if (dl.ok) iconOk = true;
+	}
+
+	// Source-specific SWF URLs
+	if (sourceSwfBaseUrl) {
+		// e.g. https://virtualc.nl/dcr/hof_furni/{rev}/{classname}.swf
+		swfUrls.push(
+			`${sourceSwfBaseUrl}/hof_furni/${rev}/${encodeURIComponent(safeSwfName)}.swf`,
+		);
+	}
+
+	// Official Habbo CDN fallbacks
+	iconUrls.push(
+		`https://images.habbo.com/dcr/hof_furni/${rev}/${encodeURIComponent(iconColorAware)}_icon.png`,
+		`https://images.habbo.com/dcr/hof_furni/${rev}/${encodeURIComponent(baseClassname)}_icon.png`,
+	);
+	swfUrls.push(
+		`https://images.habbo.com/dcr/hof_furni/${rev}/${encodeURIComponent(safeSwfName)}.swf`,
+	);
+
+	// Download icon (try all candidate URLs)
+	let iconOk = false;
+	for (const iconUrl of iconUrls) {
+		const dl = await downloadFile(iconUrl, iconPath, { validate: "png" });
+		if (dl.ok) {
+			iconOk = true;
+			break;
+		}
+	}
+
+	// Download SWF (try all candidate URLs)
+	let swfOk = false;
+	for (const swfUrl of swfUrls) {
+		const dl = await downloadFile(swfUrl, swfPath, { validate: "swf" });
+		if (dl.ok) {
+			swfOk = true;
+			break;
+		}
+	}
+
+	// ── Nitro bundle fallback: try downloading pre-made .nitro ────────
+	// If SWF download failed, try downloading a pre-made .nitro from the
+	// source's nitro base URL (many retro hotels ship .nitro bundles).
+	let nitroDownloadOk = false;
+	if (
+		!swfOk &&
+		sourceNitroBaseUrl &&
+		!existsSync(/*turbopackIgnore: true*/ nitroPath)
+	) {
+		const nitroUrl = `${sourceNitroBaseUrl}/${encodeURIComponent(safeNitroName)}.nitro`;
+		const dl = await downloadFile(nitroUrl, nitroPath, { validate: "png" });
+		if (dl.ok) nitroDownloadOk = true;
 	}
 
 	// ── Icon fallback: extract from SWF if download failed ────────────
@@ -531,7 +577,8 @@ export async function importSingleFurni(params: {
 			const iconPng = extractIconFromSwf(swfBuf, baseClassname);
 			if (iconPng) {
 				await fs.writeFile(/*turbopackIgnore: true*/ iconPath, iconPng);
-				warnings.push("Icon extracted from SWF (external download failed)");
+				iconOk = true;
+				warnings.push("Icon extracted from SWF (download failed)");
 			} else {
 				warnings.push(
 					"Icon download failed and SWF icon extraction returned nothing",
@@ -544,7 +591,7 @@ export async function importSingleFurni(params: {
 		warnings.push("Icon image download failed");
 	}
 
-	if (!swfOk) warnings.push("SWF download failed");
+	if (!swfOk && !nitroDownloadOk) warnings.push("SWF download failed");
 
 	// ── Convert SWF to Nitro ──────────────────────────────────────────
 	onProgress?.("converting");
@@ -577,8 +624,12 @@ export async function importSingleFurni(params: {
 		}
 	}
 
-	// ── Rollback: if conversion failed AND no .nitro exists, remove DB record ──
-	if (!existsSync(/*turbopackIgnore: true*/ nitroPath) && !conversionResult) {
+	// ── Rollback: if conversion/download failed AND no .nitro exists, remove DB record ──
+	if (
+		!existsSync(/*turbopackIgnore: true*/ nitroPath) &&
+		!conversionResult &&
+		!nitroDownloadOk
+	) {
 		try {
 			await db.execute(
 				sql`DELETE FROM items_base WHERE id = ${spriteId} AND item_name = ${classname}`,